tabls – Better vertical spacing in tables and arrays

Mod­i­fies LaTeX’s ar­ray and tab­u­lar en­vi­ron­ments to keep text from
touch­ing other text or hlines above or be­low. Sev­eral new
pa­ram­e­ters are de­fined and some stan­dard macros are re-de­fined.
The pack­age slows down com­pi­la­tion of ta­bles, since each en­try is
boxed twice.